A new SERS substrate based on niobium lead-pyrophosphate glasses obtained by Ag+/Na+ ion exchange

Abstract

Surface-enhanced Raman scattering (SERS) is one of the most sensitive methods for the detection of adsorbed molecules on the nanostructured coinage-metal surface. The enhancements in the order of 10 4-10 6 are routinely observed. Such an effect makes SERS spectroscopy a technique applicable to the study the adsorption of analytes in the submonolayer regime. Novel SERS sensors require novel substrates with high activity for great sensibility detection of different molecules applied in many fields, such as detections of narcotics, explosives, and molecules with biological interest. In this work, silver nanoparticles embedded in niobium lead-pyrophosphate glasses (Pb 2 P 2 O 7-Nb 2 O 5-Na 2 O) were prepared by ion exchange process, where silver ions were introduced into glass surface by Ag + /Na + ion exchange (NaNO 3 :AgNO 3 batch), and reduced to metallic silver by heat treatment at glass transition temperature (ca. 480°C). The new substrate was characterized by Raman spectroscopy, optical absorption, transmission electron microscopy (TEM) and atomic force microscopy (AFM). Its application in SERS was demonstrated by studying the adsorption of 2,2-bipyridine (bpy) on the glass surface, which has marker bands for the coordination of the adsorbate with silver atoms. The optimal surface features in terms of SERS enhancement were also discussed and the sensing ability of this new substrate was demonstrated.

Multi‐Functional Applications of H‐Glass Embedded with Stable Plasmonic Gold Nanoislands

“…Plasmonic materials possessing weak linear and nonlinear losses and high optical nonlinear coefficients are highly suitable for efficient SERS functionalities. [ 102 ] SERS is a highly efficient vibrational spectroscopy technique for identifying the analytes with high selectivity and sensitivity. [ 103 ] Nevertheless, the critical issue with the SERS technique is identifying highly stable, strongly selective, and ultra‐sensitive plasmonic substrate materials with nanoscale features.…”

Towards a Glass New World: The Role of Ion-Exchange in Modern Technology

“…Finally, it should also be mentioned that, together with these widely used glass systems, phosphate or fluorophosphate glasses are recently gaining ever-increasing interest due to their lower processing temperature, higher diffusion coefficient for noble metal ions, and better reducing properties thanks to the large concentration of non-bridging oxygens generated during the glass synthesis [99,160].…”

Phosphate glasses containing silver nanoparticles for applications in plasmonics

“…This project explored the utilization of nanoparticle-doped glasses as surfaceenhanced Raman scattering (SERS) sensors. SERS is one of the most sensitive methods for detection of compounds adsorbed to the NPs surface [38].…”

“…The conclusion that can be drawn is that, even though the laser output intensity used during the experiments was between 2 and 25% of the nominal intensity, degradation of all the compounds tested was verified, probably due to the interaction with the glass samples and the nanoparticles (which is an initial clue that the synthesized material has photocatalytic properties). Table 9 -Band assignment for solid 2,2'-bipyridine Raman spectrum [38] Raman…”